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September 2009

September 30, 2009

Daniel Goleman's blog post ("The Age of Eco-Angst") at the New York Times is interesting reading. Citing GoodGuide.com, SkinDeep.com, and the announcement of Wal-Mart's sustainability index, he writes: "These rating systems herald the death of “greenwashing,” the advertising sleight-of-hand that plucks a single virtue from a multitude of a product’s ecological impacts and touts its environmental goodness. We will no longer be impressed by an organic T-shirt if its cotton was grown by hogging water in an arid and impoverished land, or if its dye puts workers at heightened risk for leukemia, or if it was stitched together in a sweatshop where young women suffer from needless injuries."

I am not so sure that consumers can sort out the pros and cons of each product that easily and then somehow buy the best product. Of course, a retailer like Wal-Mart could give us a single number to grade the goodness of a product (somehow weighting and combining a slew of environmental and social impacts), and consumers could rely on this single number while comparing products. A more realistic and effective scenario would be for Wal-Mart and other big retailers to establish minimum standards (covering various key impacts) for product categories, and then stock only those products that pass that threshold. Anything to lessen the burden on consumers and relieve them of some of the eco-angst would be a good thing. Products that are measurably worse than the best (within a category) should never reach the stores in the first place.

Here is a case in point (not a retail example) where the choice isn't that easy. It turns out that large solar farms -- which are typically located in places that get a lot of sunlight -- may use a huge amount of water to cool the power plants. The New York Times reports that two solar farms slated to be built in Amargosa Valley, Nevada, would consume 1.3 billion gallons of water per year -- 20% of the desert valley's available water. The Times reports that conflicts over water could shape the future of many energy technologies, and the most water-efficient renewable technologies aren't necessarily the most economical. Water shortages and conflicts would of course drive the development of more water-efficient technologies, but in the short term we may have to live with a lot of angst over the renewable energy that we've waited so long to use.

A fascinating paper in Nature (Johan Rockstrom, et al)proposes a framework of "planetary boundaries" that define a "safe operating space" for humanity with respect to the Earth system, so that environmental stability of the last 10,000 years (known as the Holocene) -- which has seen human civilizations develop and thrive -- can continue for several thousand more years. The framework involves nine planetary system processes with proposed boundaries for seven of them (the other two are TBD).

Here are the processes that have already crossed their boundaries:

Earth System Process

Parameters

Proposed Boundary

Current Status

Climate change

Atmospheric carbon dioxide concentration (parts per million by volume)

350

387

Climate change

Change in radiative forcing (watts per meter squared)

1

1.5

Rate of biodiversity loss

Extinction rate (number of species per million species per year)

10

>100

Nitrogen cycle (part of a boundary with the Phosphorous cycle)

Amount of N2 removed from the atmosphere for human use (millions of tonnes per year)

35

121

The climate change boundaries result from three reasons:

Current models may underestimate long-term climate change because slow reinforcing feedback loops are not included.

The stability of the polar ice sheets are at risk when the CO2 concentration is betweek 350 and 550 ppm (based on paleoclimate data).

Some subsystems (such as ice in the Arctic ocean, and Greenland/West Antarctic ice sheets) are already moving outside their stable Holocene state.

It is hard for these standards to diverge too much, but we'll be tracking the details carefully to make sure that we can comply with all of them.

The other wrinkle is what Wal-Mart is going to do in this space -- important just because of their sheer size. Their Sustainability Consortium -- mostly university researchers -- are developing data and methodology for streamlined product life-cycle assessment (including carbon) for reporting and possibly eco-labeling applications.

Apple Computers now has a very nice website that shows the key life cycle impacts of all current products. The 20-inch iMac, for example, generates 870 Kg of CO2e over its life cycle, with 44% coming from production, 50% from usage (over a 4-year use phase), and the rest from transport and recycling. Company-wide, 38% of product carbon emissions are from production (this includes extraction of raw materials and assembly) and 53% from the use phase. The computer weighs just 8.3 Kg and the enclosure is highly recyclable.

This clearly shows the use phase contributing less to the carbon footprint compared to previous generation computers (I remember an older estimate of around 80% for the use phase), a lot of it from smarter power management. Shrinking the production emissions may be the more difficult task.